There certainly is enough land to go around for each of us! However, land is limited. Good land is even more limited. We have poverty because of the lack of access to the land and its resources.
The government gives to the powerful what mother nature provides and the rest suckle their teet. The land value tax helps level the playing field.
And Milton Friedman said he LIKED the land tax. I would say that is advocating it.
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Yes, there are taxes I like. For example, the gasoline tax, which pays for highways. You have a user tax. The property tax is one of the least bad taxes, because it's levied on something that cannot be produced — that part that is levied on the land."
http://www.wealthandwant.com/themes/quotable_nobels.htm